Artificial tooth



Oct. 12, 1937. M. G. SWENSON ARTIFICIAL TOOTH Filed Feb. 11, 1936 ATTORNEYS tooth heretofore in use.

Patented Oct. 12, 193

PATENT OFFICE,

2,095,535 ARTIFICIAL room! I Merrill G. Swenson, New York, N. Y.

1 2' Claims.

This invention relates to an anterior artificial tooth designed for mounting in a denture, and

.has for an object to provide such a tooth which is adapted for firm union with the base material of the denture so as to have greatresistance to biting strains in all directions. V

Another object is to provide a tooth of 'this character thathas a complete lingual surface which furnishes a bulk of porcelain placed so as to prevent dislodgement of the tooth and furnish additional strength as well as natural appearance and feeling tothe tongue; which tooth also has a labial surface with an abundance of overlap at the upper portion.

Another object is to provide a tooth of this character that dispenses with the necessity of usinga pin or the like as a fastening element, the unionwith the base material of the denture being accomplished by the shape of the tooth.

, Another object, is to provide a tooth of this character in which the portion that is, adapted to be set in the base'material of the denture is so.

formed as to provide depressions or retention pits for the, base material, which are so shaped as readily to accommodate the flow of the base material in the manufacture of the denture, and are of such size as to afford an abundance of strength in the union of tooth and base material. Y i

' Another. object is to provide a tooth of this characterthat is less expensive to manufacture than the anterior tooth heretofore provided with fastening pins.

Another object is to provide a tooth of this character in which the porcelain distribution is so arranged as greatly to increase the strength of the tooth with relation to the forms of pin Another object consists in providing a tooth of this character which is so shaped as to adapt itself readily to close and accurate location with respect to the edentulous ridge or gum.

A further objectjs to provide certain improve-.-

ments in the form, construction, and arrangement o1v the tooth whereby the above named and other objects may effectively be attained.

A practical embodiment of the invention is represented in the accompanying drawing in which;

v Fig. 1 represents a perspective view of the tooth detached from the denture.

Fig. 2 represents a detail front elevation, on a smaller'scal'ashowing four of the teeth set in -'the.base-materlal of the denture.

. Fig-3 represents a vertical section taken in the position differing from Fig. 1.

Application February 11, 1936, Serial No. 63,321

planeof the line III- 1H of Fig. 2 looking in the direction ofthe arrows;

Fig. 4 represents a perspective view of the detached tooth, on the scale of Fig. 1, and in a Fig. 5 represents a front elevation of tached tooth, on the same'scale.

Fig. 6 represents a side elevation of the detached tooth, on the same scale. I

Fig. 7 represents a rear elevation of the detached tooth, on the same scale.

Fig. 8v represents a top plan view of the detached tooth, on the same scale. v

Fig. 9 represents a horizontal section, taken in the plane of the line IX-IX of Fig. 6, looking in the direction of the arrows.

Fig. 10 represents a vertical section taken in the plane of the. line X'X of Fig. 7, looking in the direction of the arrows, and a Fig. 11 represents a section taken in the plan of the line XI-XI of Fig. 6, looking in the direction of the arrows. v

The front .or labial side of the tooth is denoted by l, and it is cut away at its upper portion to provide a flange or extension 2 that is fitted to enter the base material 3 of the denture to form an anchorage therein, as indicated by the dotted lines in Fig. 2. This cutting away of the front of thetooth to' form the flange 2 makes a creasethe deat the junction of the flange and labial surface,

which crease is marked 4, and serves fittingly to receive the flow of the base material during manufacture of the denture, 'so as to accomplish a smooth and natural appearing union of the parts at this point.

-' I The flange 2 extends some distance vertically upwardly beyond the labial surface of the tooth,

andgradually tapers and decreases in width as tooth.

The lingual surface of the tooth is marked 5 and it is of an extent comparable to that of a naturaltooth so as to constitute, in effect, a completelingual surface.

At the top of the lingual surface, the tooth is it progresses downwardly on each side of the only across the lingual surface but forwardly toward the central vertical axis of the tooth. As

this shoulder 6 progresses forwardly on each side cut away to form a shoulder 6 that extends not a vertical groove 8, 9, that extends away from labial portion,'and that portion to' the rear of.

said grooves may be referred to as the lingual portion.

The said grooves 8, 9 converge toward each other as they progress downwardly, and the result of the shape and relative location of the shoulder 6 and grooves 8, 9 is suchas to form, at each side of the tooth, an inwardly and downwardly tapered depression or pit which merges into the transverse passage 1 to form retention points or anchorages for the base material of the denture.

This formation of the tooth just detailed also provides a base surface that is substantially flat, though concave inside view, with undercut surrounding edges that are broken or indented, in plan view, by the upper extremities of the grooves 8, 9. The undercutting serves toreduce the area of the base portion so as to leave the lingual and labial surfaces extending therebeyond in a horizontal direction. This formation constitutes a means for accomplishing extremely flrm union of the tooth and the base material of the denture, while adapting the tooth to satisfactory use in the full range of conditions found in practice. It will be seen that the shape of the tooth lends itself to ready flowing of the base material, when in the mold or flask and under heat, into the creases, grooves, depressions, or pits, so that the base material will grip the tooth with extraordinary rigidity; The base material is adapted, even, to flowing into both sides of the passage I, and to flll the same so as to constitute endless base material reaching from one'side to the other through the tooth. The small size of the passage 1, and the flared formation at each end thereof prevents the trapping of any substantial amount of air which might hinder the union of the base material flowing in from both sides.

The setting of teeth embodying this invention in a denture may be accomplished in any well known and approved manner and, as such procedure is familiar to those skilled in this art, there seems no occasion for describing it.

When suitably set in a denture, teeth embodying this invention have a very natural appearance, a very pleasing surface for contact with tongue and lip, a very natural and effective biting action, and extraordinary resistance to all strains engendered during mastication. Each tooth exhibits to a marked degree all the advantages set forth in the statement of this specification.

It will be understood that various changes may be resorted to in the form and arrangement of the several portions of the tooth, without departing from the spirit and scope of my invention, and hence I do not intend to be limited to the details herein shown and described, except as they may be included in the claims.

What I claim is:

I l. An'anterior artificial tooth having substantially complete lingual and labialsurfaces and a substantially complete base portion having a base wall extending from the labial gingival to the lingual surface, the labial portion being formed with a substantially vertical inner wall extending inwardly from the mesial and the distal sides and the lingual portion being formed with an incisally inclined inner wall extending from the mesial and distal sides and intersecting said inner labial wall, and the mesial and distal side walls of the base portion tapering inwardly toward said incisal portion from said base wall and intersecting said labial and lingual inner walls, thereby forming an inwardly and incisally tapered recess at each side of the tooth, said recesses being suited readily to receive the flow of the base material of of objects at the outset the denture during molding, whereby the tooth is firmly interlocked in the denture by a pair of tapered gripping projections composed of the denture base material.

2. An anteriorartificial tooth having substantially complete lingual and labial surfaces and a substantially complete base portion having a base wall extending from the labial gingival to the lingual surface, that portion of the base wall to the rear of the labial portion of the tooth being.

reduced substantially in width, the labial portion of the tooth being formed with a substantially vertical inner wall extending inwardly from the mesial and the distal sides and the lingual portion of the tooth being formed with an incisally inclined inner wall extending from the lingual gingival toward the incisal edge and from the mesial and distal sides and intersecting said inner labial wall, and the mesial and distal side walls of the base portion tapering inwardly toward said incisal portion from said base wall and intersecting said labial and lingual inner walls, thereby forming an inwardly and incisally tapered recess at each side of the tooth, said recesses being suited readily to receive the flow of the base material of the denture during molding, whereby the tooth is firmly interlocked in the denture by a pair of tapered gripping projections composed of the denture base material.

MERRILL G. SWENSON. 

